Background: Recent research demonstrates the critical impact that cytokine storm and intensive immune response against the virus play in worsening the severity and death of illness. Biomarkers such as Procalcitonin (PCT), Serum Amyloid A (SAA) play a part in the etiology of severe COVID-19 and may serve as an early indicator for severity. Objective: The current study aimed to determine the serum concentrations of these laboratory biomarkers (PCT and SAA) in asymptomatic, moderate, severe and critical COVID-19 patients and to compare them to healthy controls. Patients and methods: A total of 100 patients by positive RT-PCR COVID-19 results besides a control group of 46 healthy participants with negative RT-PCR results. Patients were classified as 4 groups; critical, severe, moderate, or asymptomatic, according to WHO standards. Enzyme-Linked Immune Sorbent Assay (ELISA) was used by (CV Human Reader HS REF 16670) to measure PCT and SAA. Results: Mean level of PCT is 404.59 pg/ml and SAA 19.1 pg/ml among patients more than controls (127.65 and 10.64, respectively). Mean levels were higher among both PCT and SAA in critical (680.84 and 28.46, respectively) and severe (565.86 and 23.27, respectively) of other than moderate (226.98 and 13.71, respectively) and asymptomatic (144.67 and 10.75, respectively). Conclusion: There was a major alteration in the level of PCT and SAA among patients groups (critical, severe, moderate, and asymptomatic) and control group. A strong correlation was found between biomarkers high concentrations, old age, and chronic diseases with the disease severity.

Background:-M. pneumoniae is an important human pathogen that produces community-acquired respiratory tract infection. Diagnosis of M. pneumoniae infection is challenging and crucial for the timely initiation of the effective antibiotic therapy.Objective: This study has been undertaken to detect M. pneumoniae in respiratory samples (throat swabs, throat wash and sputum) in patients with respiratory tract infection qualitatively by conventional polymerase chain reaction (PCR). Also, more advanced one, real time PCR was used to determine mycoplasmal target gene qualitatively and quantitatively.Patients and methods: The study was performed on Seventy-five patients and thirty healthy subject as control. Genomic DNA was extracted and M. pneumoniae target gene (lipoprotein gene) was amplified using conventional PCR. Negative, positive controls and internal controls were involved in each experimental run. The amplified products were analyzed in 2% agarose gel and visualized using Red safe staining. In real time PCR, specific primer and probe mix depending on TaqMan® principle was used to detect P1 adhesion gene through FAM channel. A fluorogenic probe was included in the same reaction mixture which consists of a DNA probe labeled with a 5`-dye and a 3`-quencher. During PCR amplification Data were analyzed using Smart-cycler software and M. pneumoniae DNA copy number was estimated from the cross point threshold relative to positive standard.Results: Thirty five patients(45.5%) were positive by PCR and Thirty two (42.6 %) were positive by Real-time PCR. The highest rate of infection by using tow molecular methods were of less than 20 years of age. The quantity of M. pneumoniae DNA target gene in positive Real-time PCR were ranged between 10-2000copies/μl.Conclusion: The study concluded that both of molecular techniques conventional and real-time PCR are a rapid, reliable and ideal in diagnosis of M. pneumoniae using throat swabs, throat wash and sputum samples.